OV-10 Bronco Twin Looses Engine (again)

[wannabe]

This is my Nitromodels OV-10 Bronco ARF. Many of you have seen the build thread with retracts here (http://www.rcgroups.com/forums/showthread.php?t=475564&pp=50&highlight=bronco) .

I had not flown it since last summer because I kept loosing an engine after about 4 minutes of flight. This twin plane can fly almost perfectly on a single engine, though many don't believe it. Well through some deductive reasoning I realized that my 1st Gen TP4200 3S just wasn't up to snuff after a few minutes and drop voltage until one of my engines died, the, it was able to keep the other one going long enough to do a pucker landing.

I fixed it with a Polyquest 4S 4400 "twenty" pack. That worked like a charm! I finally got some excellent flight times today and this is one of the smoothest planes I have.

Last flight of the day, halfway through or there abouts, we hear a buzz and smack, then see one of my props, spinner and all, go floating to the ground. Luckily I had our club photographer shooting my flight. I could not tell which prop i lost and theplane was turing away from me a little sluggish. I tried full left rudder and nothing happend so I figured I would come around to the right and bring it back. Problem was, trees in the way, so I flew it to avoid the trees with the same motions I use when both motorsare running and is snapped real sharp to the right. After I swallowed my testcle, I let go of the sticks and let the nose drop then just pulled out of the dive and flew back home for a perfect landing.

Funniest thig was the 6 guys in the pits yeling out completely usesless directions and one guy was tell me to giv it up and try to crash soft. I have had engines out on this plane before and it aint goin in without a fight. I won this time.

-Todd

[mdlifcrisis]

Those pictures are super!
Glad ya got it back in one piece..

[Edd Spidell]

Hey Todd!,

Now that's the way to do it - plus you have the photos to go along with it!

Seriously, very nice recovery in spite of the "field experts..."

Best regards,

Edd

[wannabe]

Thanks guys!

Hey Edd, I bet your Mirage-o-meter is high and dry....

-Todd

[Sluf7]

Nice Job.

[Murocflyer]

Ummm, you missed the runway. :p

Great recovery and great photos.

[wannabe]

Ummm, you missed the runway. :p



Now you sound like a Pit Critic ;)

[Smash McCrash]

Nice that you ignored the pit critics and brought it home. I have seen someone listen to them and had repairs afterward. Better to just go with what you know, then you can blame nobody but yourself...

Nice pics!

Mike

[wannabe]

Thanks,

The point of this thread was to broadcast the excellent stability of this twin engine ARF. Other twin engine planes do not have the stabilty this one has when flying on one engine. The only reason this one snap-rolled is becuase I was using full control inputs for a brief second trying to aviod the trees. With this plane, if you loose an engine, careful control inputs keep it flying safely with no real bad tendancies.

One time last summer, I flew half a pack before I even knew I had lost an engine! :eek: I thought to myself, "boy, this thing is kind of underpowered" and then I heard a Pit-Critic say, "wow, he is only using one prop". Boy was that a surprise.

Nitroplanes has these on sale now for $89 in four different colors. I would swap this one for a cammo version but I already have too much work in this one because of the retracts. Besides, there are too many warbirds at my field already.

-Todd

[Tram]

That thing looks really good in the air.. :)

[DavidN]

What motors are you using and what glow size was the plane intended for?

Looking for a twin for 2 hacker A50 10s on 4s.
DavidN

[wannabe]

What motors are you using and what glow size was the plane intended for?

Looking for a twin for 2 hacker A50 10s on 4s.
DavidN

David, the build thread is here (http://www.rcgroups.com/forums/showthread.php?t=475564&pp=50&highlight=bronco) . In brief, I used geared 400s. The model is made for .15 to .20 glow engines.

Nitro models has them on sale here: http://www.nitroplanes.com/15.html

-Todd

[Edd Spidell]

Hey Todd,

Happy New Year!

Well, after reading the postings and your great short story, I decided to buy one also, and have the camo version on the way. I will power this one with AXI 2814/10's and give it to my juniors at school when it grass is green again. Still no snow, a very strange year.

Regards,

Edd

[SCALEFAN]

Todd,

I second that. You almost convinced me to get one. In order to protect myself I had to shut off the internet, pull the telephone out of the wall, and epoxy my wallet shut.

Will the plane fly with 2820 motors? Of course it will, I just was thinking that if things become un-glued.............. :eek:

Edd, it's so cold here in Southern California, that I was thinking about coming to RI to get warm. :D

Al

[wannabe]

Al and Edd,

You guys will be happy with this plane. It flies very well with no real bad tendancies.

Al, at the rate you are cranking through P-61s this build will only take a couple of hours for you ;)

Some noteworthy observations:

I re-read my build thread last night and saw where I had mentioned that I thought my power setup was marginal. The geared 400 motors I have in mine are little power-houses so the motor and prop combo was never an issue. The lack of power was surely due to my first gen ThunderPower 4200 pack. That pack was the reason I kept loosing an engine after about 4 minutes of flight. I had owned that pack since the early days of Lipos (ahhh remember when.....).

Since I have tried new packs I find my performance is perfect with plenty of emergency power to spare. Just an FYI.

C'mon Al, time to start multitasking....

-Todd

[Skip D]

This is my Niromodels OV-10 Bronco ARF. Many of you have seen the build thread with retracts here (http://www.rcgroups.com/forums/showthread.php?t=475564&pp=50&highlight=bronco) .

I had not flown it since last summer because I kept loosing an engine after about 4 minutes of flight. This twin plane can fly almost perfectly on a single engine, though many don't believe it. Well through some deductive reasoning I realized that my 1st Gen TP4200 3S just wasn't up to snuff after a few minutes and drop voltage until one of my engines died, the, it was able to keep the other one going long enough to do a pucker landing.

I fixed it with a Polyquest 4S 4400 "twenty" pack. That worked like a charm! I finally got some excellent flight times today and this is one of the smoothest planes I have.

Last flight of the day, halfway through or there abouts, we hear a buzz and smack, then see one of my props, spinner and all, go floating to the ground. Luckily I had our club photographer shooting my flight. I could not tell which prop i lost and theplane was turing away from me a little sluggish. I tried full left rudder and nothing happend so I figured I would come around to the right and bring it back. Problem was, trees in the way, so I flew it to avoid the trees with the same motions I use when both motorsare running and is snapped real sharp to the right. After I swallowed my testcle, I let go of the sticks and let the nose drop then just pulled out of the dive and flew back home for a perfect landing.

Funniest thig was the 6 guys in the pits yeling out completely usesless directions and one guy was tell me to giv it up and try to crash soft. I have had engines out on this plane before and it aint goin in without a fight. I won this time.

-Todd
-Awesome job Todd!!!!!! and sweet looking airplane. Skip D

[ggcrandall1]

Todd,

Great save on the motor out.

I got sidetracked on my OV-10 last year and finally got it flown in late October. I wasn't the pilot and a good thing. The plane was tail heavy and lacked power (props too small). Also had problems with the ESC's (motors intermittent). My pilot got it down mostly OK. Tore out the nose wheel and nose cone. When I got it home I set it aside. Now I have rebuilt the nose gear and made a new nose cone of fiberglass. However I cannot locate the manual to verify the correct CG. Can you look the CG up for me? Thanks.

BTW how do you access your battery? I am going in through the canopy but I thought in the old build thread you mentioned going in through the tail cone.

Glen.

[SCALEFAN]

Todd,

Regarding multi tasking. Last week while doing the second P-61, I also put together the Hangar 9 P-51, and the Hangar 9 P-47. Then I balanced all 4 airplanes, the B-25, the two Hangar 9 planes, the P-61. One week, that's it. Sick, sick sick, sick :eek:

Now, don't cut yourself short, you're no slouch when it comes to building planes. Based on what you posted, the OV-10 does not appear to be a piece of cake to complete when retracts are added. If I remember correctly your build thread was pretty complex and was very good. You actually had a flying video. Not only that, you built and flew other planes at the same time. Hat's off to you. Obviously, you guys in Vacaville have alot of spare time on your hands. :D

Al

[tdearth]

Just curious Todd.
When you flew with just one motor because you threw a prop, didn't the other motor over rev to the point of distruction at full power and no prop on it?

A motor shutting down is one thing. Losing a prop is another.

Tim

[wannabe]

Al,

No spare time. Running out of room, too.

...and I thought I have OCD..



Tim.

Good question. Most of the time, the throttle was cut, or was being carefully nursed into an optimal speed. So I dont think the starboard motor got over revved. I bench tested both motors and everthing seems fine. I am using Mega motors and high-quality Mega inner-driven gear boxes.


-Todd

[tdearth]

Boy, talk about a dummy. I ordered a yellow one and was going to paint it
camo because I didn't want yellow but thought that was all they had.
After seeing someone post about the different versions I went back and ordered a camo kit.

I will have a yellow bronco for sale cheap when it arrives. :o
It was too late to cancel that order.

Tim

[ggcrandall1]

Tim,

How cheap? PM me a price.

Glen

[wannabe]

Todd,

BTW how do you access your battery? I am going in through the canopy but I thought in the old build thread you mentioned going in through the tail cone.

Glen.

Glen,

I had to build a shelf over the nose gear retract mechanism to place the 4S battery in a balanced place. I hate adding lead to balance. I still accsess through the tail cone like I did with the first pack.

-Todd

[ggcrandall1]

Todd,

What battery are you using?

I am using a Polyquest 20 4s1p3100. I also built a battery tray over the nose gear servo. I am not using retracts so the nose wheel is on the nose bulkhead. My mega 1615/4's draw about 20 amps each at WOT so I may have to add my second battery in parallel for decent flight times.

I am accessing the battery through the canopy. I am working up a magnetic attachment for it.

Where is your CG?

Glen

[wannabe]

Glen,
My pack is a 4400 Polyquest.

I am using the same motors but with 3:1 gearboxes. I would be careful with direct drive on this plane with those 4 turn Megas. Especially with 4S! I reccomend that you use gearboxes or use 3S.

My CG is at the factory spec.

-Todd

[xfly-er]

Wannbe did you find out exactly what happened to the prop? Did the prop adapter come off the motor shaft? & what might have caused the problem.

[wannabe]

Wannbe did you find out exactly what happened to the prop? Did the prop adapter come off the motor shaft? & what might have caused the problem.

It was a collet adapter that apparently wasn't tight enough. If you over tighten the collets, they are hard to remove sometimes. I must have only torqued that one on just a little over finger tight. Also, I had been flying it on 3S and when I switched to a 4S pack, the extra RPM/thrust must have yanked it off. No big.

-Todd

[wannabe]

I have more adventures with the Bronco than with any of my planes.

Flying formation with two twin engine planes is fun and a great spectacle to see for the crowd. It is even better when the 4lb Bronco chops the 1.5lb foam P-38 to bits.

Mike: "What was that? What happened?!"

Todd: "Um...You hit a bird?"

Mike: "I hit a bird?! What bird, did I kill it? Where are all the pieces of my plane floating?!"

Todd: "Over there. and there.....and there... Some are in the jet-stream and will never land..."

Mike: "Did we hit?!"

Todd: "Um...Maybe. I am still flying fine.."


I make a couple of low passes to check. I climb slowly and put the gear down. and landed. I had absolutely no damage to the Bronco but there was silver paint on the leading edge of the left prop and spinner. Also on the left wing tip.

Mike and I are now even. A few months ago I was doing touch-and-gos on the runway, into the wind, with my Vermont Bell. Mike was speed running his foam Alpha Saber-jet downwind, low over the runway. Our planes collided head on in two opposing vectors that could not have been more perfect. The Vermont Belle is totalled. His jet flew again the next weekend.

Today the tables turned and the balsa wins over foam.

-Todd

[wannabe]

I cant believe no one has commented about the loss of an FSK P-38.....

Mike still does not believe we hit. It sure seemed that way to me.

-Todd